Hide more newtype machinery

Author: Luka Jacobowitz

core/src/main/scala/cats/data/NonEmptyMapImpl.scala

@@ -23,14 +23,14 @@ import cats.{Always, Apply, Eval, Foldable, Functor, Later, NonEmptyTraverse, No
 
 import scala.collection.immutable._
 
-private[data] trait Newtype2 { self =>
-  type Base
-  trait Tag extends Any
-  type Type[A, +B] <: Base with Tag
+trait Newtype2 { self =>
+  private[data] type Base
+  private[data] trait Tag extends Any
+  private[cats] type Type[A, +B] <: Base with Tag
 }
 
 
-object NonEmptyMapImpl extends NonEmptyMapInstances with Newtype2 {
+private[data] object NonEmptyMapImpl extends NonEmptyMapInstances with Newtype2 {
 
   private[cats] def create[K, A](m: SortedMap[K, A]): Type[K, A] =
     m.asInstanceOf[Type[K, A]]
@@ -241,8 +241,6 @@ private[data] sealed class NonEmptyMapOps[K, A](val value: NonEmptyMapImpl.Type[
   def show(implicit A: Show[A], K: Show[K]): String =
     s"NonEmpty${Show[SortedMap[K, A]].show(toSortedMap)}"
 
-  override def toString: String = s"NonEmpty${toSortedMap.toString}"
-
   /**
     * Typesafe equality operator.
     *

laws/src/main/scala/cats/laws/discipline/Arbitrary.scala

@@ -80,7 +80,7 @@ object arbitrary extends ArbitraryInstances0 {
       a <- A.arbitrary
     } yield NonEmptyMap((k, a), fa))
 
-  implicit def cogenNonEmptyMap[K: Order : Cogen, A: Order : Cogen]: Cogen[NonEmptyMap.Type[K, A]] =
+  implicit def cogenNonEmptyMap[K: Order : Cogen, A: Order : Cogen]: Cogen[NonEmptyMap[K, A]] =
     Cogen[SortedMap[K, A]].contramap(_.toSortedMap)
 
   implicit def catsLawsArbitraryForEitherT[F[_], A, B](implicit F: Arbitrary[F[Either[A, B]]]): Arbitrary[EitherT[F, A, B]] =

tests/src/test/scala/cats/tests/NonEmptyMapSuite.scala

@@ -42,7 +42,7 @@ class NonEmptyMapSuite extends CatsSuite {
   }
 
   test("Show is formatted correctly") {
-    val nonEmptyMap = NonEmptyMapImpl("Key" -> "Test", SortedMap.empty[String, String])
+    val nonEmptyMap = NonEmptyMap.one("Key", "Test")
     nonEmptyMap.show should ===("NonEmptySortedMap(Key -> Test)")
   }
 
@@ -169,23 +169,23 @@ class NonEmptyMapSuite extends CatsSuite {
 
   test("fromMap round trip") {
     forAll { l: SortedMap[String, Int] =>
-      NonEmptyMapImpl.fromMap(l).map(_.toSortedMap).getOrElse(SortedMap.empty[String, Int]) should ===(l)
+      NonEmptyMap.fromMap(l).map(_.toSortedMap).getOrElse(SortedMap.empty[String, Int]) should ===(l)
     }
 
     forAll { nem: NonEmptyMap[String, Int] =>
-      NonEmptyMapImpl.fromMap(nem.toSortedMap) should ===(Some(nem))
+      NonEmptyMap.fromMap(nem.toSortedMap) should ===(Some(nem))
     }
   }
 
   test("fromMapUnsafe/fromMap consistency") {
     forAll { nem: NonEmptyMap[String, Int] =>
-      NonEmptyMapImpl.fromMap(nem.toSortedMap) should ===(Some(NonEmptyMapImpl.fromMapUnsafe(nem.toSortedMap)))
+      NonEmptyMap.fromMap(nem.toSortedMap) should ===(Some(NonEmptyMap.fromMapUnsafe(nem.toSortedMap)))
     }
   }
 
   test("fromMapUnsafe empty map") {
     val _ = intercept[IllegalArgumentException] {
-      NonEmptyMapImpl.fromMapUnsafe(SortedMap.empty[String, Int])
+      NonEmptyMap.fromMapUnsafe(SortedMap.empty[String, Int])
     }
   }